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Throttle Body sizing

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I know this question gets asked a lot, but I am stuck deciding between 2 DBW Throttle Body sizes.

From what I have read online and calculated, I should use about 87mm ID Throttle body. But we know that is not a common size.

So here's the short version:

Fully built v6 3.7L, Darton MID Sleeves, Pistons, Rods, Cams, Oversized Valves, Ported heads, ect ect ect

7975mm Turbo with 1.28 rear housing

Haltech Nexus R5

Custom built Intake Manifold with rather long runners (This is because of the location, not a desired choice).

I have 2 Throttle bodies:

Mopar Hellcat 92mm and a Bosch 82mm Throttle Body

The target is a little over 1200 WHP, but I would still like throttle resolution / response.

Question 1

Will the 82mm be sufficient for my goals, or should I just use the 92mm?

Question 2

The next issue is what size boost piping do I then use from the Intercooler to the Throttle Body, as the common Aluminum pipe sizes are 3"(76mm) or 3.5" (89mm)

Ideally I would have like to use 3.25" (82.5mm) If I end up using the 82mm but I cant seem to find that locally in NZ


I would recommend the 82mm turbo. I have been involved with many 2.8-3.4L 6 cylinder applications running 12-1500hp that had no issues with the 82mm throttle.

My only objection with the bosch throttles is they have a tendency for a noisy position signal in high vibration environments as the connector on them isnt the best in these scenarios. Normally they get a fly lead and potted, or moved into the intercooler pipe supported by clamps like plazmamann or vibrant.

82mm and 3" IC pipe will be fine at 1200 HP as long as pipe routing is reasonable.

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